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The phosphorus and zinc contained in zinc dialkyl dithiophosphate (ZDDP) caused severe environment pollution and catalyst poison. Thus, the phosphorus-free additive, such as borate esters, has become one of studying hot topics in the area of oil additive. However, the stability of hydrolysis greatly limited the use of borate esters. The purpose of this paper is to improve the stability of hydrolysis by synthesizing a new kind of N-containing heterocyclic borate ester (MTTDB) as a lubricant additive.

The tribological properties of novel borate ester (MTTDB) as an additive in the base oil were studied by a four-ball machine. The element composition and chemical state of the tribofilm were investigated by scanning electron microscopy, energy dispersive spectrometer and X-ray photoelectron spectroscopy.

The results showed that the base oil lubricated by MTTDB exhibited high hydrolytic stability, good anti-wear property and excellent extreme pressure performance. When 2.5 per cent MTTDB was added into the 100N base oil, the smallest wear scar diameter (0.46 mm) was obtained. Furthermore, the decomposed borate ester, organic sulfide adsorbed on the worn surface was detected, and S element reacted with the steel surface and generated FeSO4, both of which contributed to the formation of the tribofilm.

Based on N-containing heterocyclic compounds, for instance, thiadiazole derivatives, introducing nitrogen and sulfur elements into borate ester, a new kind of N-containing heterocyclic borate ester (MTTDB) exhibited excellent property in hydrolysis stability, friction-reducing, anti-wear and extreme pressure. This synthesized method would be helpful for the borate ester used as additive in engine oil, gear oil and other industrial lubricants.

This paper aims to find a new method that could be applied to the high and mid-grade prosthesis knee joint.

Based on analysis, calculation, modeling, simulation and experimental study of the motion law of knee joint, this paper not only determines the structure and parameters of the knee joint and calculates the instantaneous center but also analyzes the stance stability and completes the optimization. With the help of experimental tests (fatigue test and gait curve test), the quality and performance of the designed knee joint is verified.

The experimental results show that the gait curve of the designed knee joint is much closer to health people. The designed prosthesis knee joint, with adjustable swing speed and gait curve which are close to health limb, has a better performance when compared to the ordinary knee joint with four-bar linkage structure.

This paper developed a prosthesis knee joint based on a novel design method that could be applied to the “high and mid” grade prosthesis knee joint and verified its function on an amputee performed the lower amputation, which could provide theoretical support for researches and designs related to prosthesis knee joint in future.

The purpose of this paper is to test the mediating role of perceived insider status (PIS) on the relationship between differential leadership and thriving at work, and the extent to which this mediating role is moderated by proactive personality.

This study conducts a questionnaire with 332 employees from China, taking certain traditional cultural factors and social exchange theory into consideration. This paper then analyzes the responses using a structuring equation model with SPSS 24.0 and LISREL 8.7.

The results show that PIS mediated the relationship between differential leadership and thriving at work. In addition, proactive personality was found to moderate this mediating pathway, whereby a high proactive personality increased the mediating role of perceived insider status.

This study explores how and why differential leadership is positively related to thriving at work. This paper verifies the moderated mediation model relationship among the research variables and contributes to the literature on differential leadership.

Introduction: The insurance industry has unprecedented growth, and the demand for insurance has outgrown in the recent past due to the prevailing pandemic. The companies have a large base of the data set at their disposal, and companies must appropriately handle these data to come out with valuable solutions. Data mining enables insurance companies to gain an insightful approach to map strategies and gain competitive advantage, thus strengthening the profits that will allow them to identify the effectiveness of back-propagation neural network (BPNN) and support vector machines (SVMs) for the companies considered under study. Data mining techniques are the data-driven extraction techniques of information from large data repositories, thus discovering useful patterns from the voluminous data (Weiss & Indurkya, 1998).

Purpose: The present study is performed to investigate the comparative performance of BPNNs and SVMs for the selected Indian insurance companies.

Methodology: The study is conducted by extracting daily data of Indian insurance companies listed on the CNX 500. The data were then transformed into technical indicators for predictive model building using BPNN and SVMs. The daily data of the selected insurance companies for four years, that is, 1 April 2017 to 21 March 2021, were used for this. The data were further transformed into 90 data sets for different periods by categorising them into biannual, annual, and two-year collective data sets. Additionally, the comparison was made for the models generated with the help of BPNNs and SVMs for the six Indian insurance companies selected under this study.

Findings: The findings of the study exhibited that the predictive performance of the BPNN and SVM models are significantly different from each other for SBI data, General Insurance Corporation of India (GICRE) data, HDFC data, New India Assurance Company Ltd. (NIACL) data, and ICICIPRULI data at a 5% level of significance.

To solve the problem of meminductor in circuit design, this paper aims to describe a synthesis method and the mechanism in terms of constitutive relation of the gyrator for transforming nano memristor into meminductor.

The gyrator was designed to achieve memristor-meminductor transformation by using amplifiers and memristor.

The simulation results verify the flexibility of its operation.

This gyrator can be used in integrated circuit design such as filter, diplexer, and it has a simple and economical implementation.

This paper aims to propose the modeling of nanostructured memristor, and the circuit of amplitude modulator was designed and analyzed with memristor. The simulation results show that the nanostructured memristor can be utilized to implement the desired amplitude modulated signal.

The modeling of nanostructured memristor is proposed in this paper, and the circuit of amplitude modulator was designed and analyzed with memristor, amplifiers and BPF device. For measuring the modulated signal, the emulator circuit of memristor is designed. The simulation results show that the nanostructured memristor can be utilized to implement the desired amplitude modulated signal.

The innovations of this work are as follows: the AM modulator circuit using memristor has been proposed, analyzed and simulated. The emulator of memristor is given.

The innovations of this work are as follows: the AM modulator circuit using memristor has been proposed, analyzed and simulated. The emulator of memristor is given, and the results of this work demonstrate that the nonlinearity of the memristor can be used to generate the desired amplitude modulation free of harmonic sidebands, because of distortion of the modulating signal.

This annotated list represents a selection of outstanding poetry titles published in the USA in 2003 and the early part of 2004.

The authors selected the titles in this list from the 2,100 titles received for the 2004 Poetry Publications Showcase at Poets House in New York City, held in April 2004.

The authors selected titles for this list that would be both accessible and challenging to library users.

This list can be used as a guide to collection development for contemporary poetry.

Professional touching behavior (PTB), defined as intentional touching behavior that occurs between organizational members and that falls within the boundaries of appropriateness and professionalism in the workplace, is prevalent in organizations. Scholars from multiple disciplines, including human resources researchers, have acknowledged the importance of physical contact for facilitating interpersonal communication and relationship-building. However, PTB may not only elicit positive reactions from those who receive it but also negative reactions as well, with implications for social dynamics in organizations. PTB can, on the one hand, fulfill employees’ desires for interpersonal connection; at the same time, such physical contact at work can represent a threat to employees’ health. To explain the nature and implications of these divergent effects of receiving PTB, the authors draw upon sociometer theory and behavioral immune system (BIS) theory to model the emotional, cognitive, and physiological processes via which, and the conditions under which, receiving such behavior will result in socially functional responses and prompt subsequent prosocial behavior, and when PTB will be perceived as a health risk and prompt withdrawal behavior. The theoretical framework of this chapter expands our conceptual understanding of the consequences of interpersonal physical contact at work and has important human resources management (HRM) implications for organizational managers.